Pyrolysis and Coke Deposition of JP-10 with Decalin in Regenerative Cooling Channels

The application of JP-10 (exo-tetrahydrodicyclo-pentadiene) in regenerative cooling channels is restrained by the severe coke deposition during its supercritical pyrolysis, while using hydrogen donors is one of the coke deposition suppression methods. To get new insights into the possible coke inhibition effect of the hydrogen donor under supercritical conditions, the pyrolysis and coke deposition ofJP-10 in the presence of decalin at different concentrations (10-30 wt %) were experimentally examined in an electrically heated tube reactor at 4.0 MPa and 550-730 degrees C. The addition of decalin promotes the pyrolysis of JP-10, and the heat sink is maximumly improved from 2.87 to 3.21 MJ/kg (11.6%) at 730 degrees C, attributed to the higher conversion and mole yield of light alkenes. Meanwhile, the coke on the surface and in the bulk flow was maximumly reduced 43.0 and 31.8% with the addition of decalin, respectively. The coke deposition suppression is in agreement with the increased selectivity of stable precursors and the reduced content of polycyclic aromatic hydrocarbons (PAHs). On the basis of product distributions, decalin provides more free radicals to enhance the bimolecular reaction, then promotes the conversion of JP-10, and also provides active hydrogen radicals to restrain the formation of PAHs in the bulk flow and the radical growth of surface coke.